This invention relates to a rotary joint between a stationary sleeve and a rotary liquid conduit. The conduit may, for example, be part of (or contained within) a rotating roll used in paper mills to perform calendaring operations on paper stock; water circulated through the rolls maintains them at desired temperatures suitable for achieving uniform quality paper.
Rotary liquid conduit joints are already known. In one case a rotary liquid conduit was provided with an annular ceramic disc on its end surface. A mating disc, formed of carbon graphite material, was provided in the stationary housing that contained the bearings for the rotary conduit. One disadvantage of this arrangement is that the ceramic disc and graphite disc are located within the housing where it is difficult to gain access for repair or replacement purposes. Another disadvantage is that the sealing discs are non-adjustable. Once the disc system begins to leak the only corrective action that can be taken is to replace the disc assembly. Often a considerable time is involved in removing and replacing the bearing and seal components with resultant substantial costly down-time of production operations. A further disadvantage of the ceramic-graphite disc assembly is the cost; these disc assemblies are relatively costly. A still further disadvantage of the prior art arrangement is the fact that the seal assembly is in close proximity to the anti-friction bearings. Water leakage past the seals can corrode the bearings.